Mich. Comp. Laws § 42.3
The proposition to incorporate as a charter township shall be submitted at the next general or at a special election in the event that, on or before August 30, or, in the event of a special election, not less than 60 days, preceding such election, the township board shall vote to submit such proposition to the electors of the township, or in the event that there shall be filed with the township clerk on or before such date petitions requesting the submission of such proposition which have been signed by a number of electors of the township which shall not be less than 10% of the total vote cast for supervisor in the township at the last election in which a supervisor was elected. The township clerk shall check the signatures on such petitions with those of the electors signing such petitions as they appear on the registration cards of the township and, if such petitions bear the required number of signatures of electors of the township, shall do and perform all acts required for the submission of the proposition to become a charter township at the next general or special election.
MCL 42.3